Face transplantation is a promising experimental surgery for patients with severe facial disfigurement. In face transplantation, a severely disfigured Recipient receives a transplant of healthy facial tissues from a Donor. The transplanted tissues may include nose, lips, teeth, skin, bone, blood vessels, muscles and nerves, among others. A major ethical concern in face transplantation is the lack of understanding on how much of the facial appearance of the Donor is transferred to the Recipient (undesirable), and how much the Recipient looks after the surgery like he/she did before the disfigurement (desirable). These outcomes are defined as appearance transfer and appearance persistence, respectively. Addressing these concerns is crucial for the future of face transplantation, because the prospect of appearance transfer may discourage Donor families to donate the facial tissues, and generate worry and anxiety in the Recipients. Unfortunately, these concerns cannot be addressed [with statistical significance] in real face transplantation Donors and Recipients, because there are so few in the world, and because [their identities are confidential]. This study proposes to perform virtual face transplantation (VFT) to test the hypothesis that appearance transfer from Donor to Recipient in face transplantation is low. 3D computer models of real human adult heads will be created from existing computer tomography data in the clinical archives of Brigham and Women's Hospital. 100 VFTs will be performed across these 3D models, and 20 independent Reviewers will evaluate the resemblance of post-transplant faces to Donors and Recipients. The Specific Aims are: 1. To estimate appearance transfer after VFT. Reviewers will assess whether each post-transplant face: (a) looks a lot like the Donor, (b) looks a little like the Donor, (c) does not look like the Donor, or (d) not sure. Large numbers of (a), (b), (c) or (d) answers respectively indicate: significant, moderate, low or inconclusive appearance transfer. 2. To estimate appearance persistence after VFT. Reviewers will assess whether each Post- transplant face: (a) looks a lot like the Recipient, (b) looks a little like the Recipient, (c) does not look like the Recipient, or (d) not sure. Large numbers of (a), (b), (c) or (d) answers respectively indicate: significant, low, moderate or inconclusive appearance persistence. 3. To determine if age and/or gender of the Recipient of VFT affect appearance transfer and/or persistence. VFTs will be performed in Recipients grouped by gender (male or female) and age (20- 29, 30-39, 40-49, 50-59 and 60-69 years old), and it will be determined whether appearance transfer and persistence depend on the age and/or gender of the Recipient. PUBLIC HEALTH RELEVANCE: Face transplantation has emerged as a powerful approach to treat the most severe cases of facial deformity. However, a major ethical issue in face transplantation research is the transfer of facial appearance from the Donor to the Recipient, which heavily influences the informed consent process of the Donor's family, may negatively affect facial tissue donation and generates worry and anxiety in the Recipient. [Addressing this ethical issue is critical for the future of face transplantation].